In recent years, preventive medicine, early diagnosis, and early treatment have become more important in medical treatment. Specifically, automated instruments, “point of care” (POC), “near patient testing”, and molecular detection are being used substantially.
According to a report of global molecular detection, the output of consumption of the global molecular detection market will be increased to 15.5 billion in 2015 and 42.5 billion in 2019. The average growth rate of the market will be up to 11.5% in 2015 and 22.4% in 2019. Therefore, there are enormous opportunities and aspects to be developed in the molecular detection market.
At present time, there have been thousands of biomarkers and biomarker candidates published in journals or patent applications, and the numbers keep increasing. Before the end of February 2010, 913 biomarkers were filed as US patent applications and 76 biomarkers were granted. In addition, 450 biomarkers were applied on clinical molecular medicine. In the future, medical care will pay more attention on the molecular medicine so as to serve personalized medicine, e.g., medical safety screening, medical efficacy tracking and so on. Thus, personalized health care will become a novel trend.
Also, World Health Organization (WHO) proposed some standards for an ideal molecular diagnosis system. According to the standards, each diagnosis should satisfy 7 requirements abbreviated as “ASSURED”, which is an acronym for: “Affordable”, “Sensitive” (less false negative), “Specific” (less false positive), “User-friendly”, “Rapid and robust”, “Equipment-free”, and “Deliverable to end-users”.
Regarding to a standard process of genetic screening in the laboratory, multiple pre-treatments (e.g., forming bonding between blood and the antibodies, cleaning the analyte, forming bonding between the analyte and the antigens) needs to be performed after the analyte is obtained (e.g. whole blood samples, larynx samples and the like) in the standard procedures. Only after the pre-treatments are performed, nucleic acid amplification may be performed (e.g., polymerase chain reaction or methylation-specific polymerase chain reaction). Finally, the genes are identified (e.g. by real time polymerase chain reaction or by electrophoresis). It is easy to find out the above-mentioned process is time-consuming as well as relying on professional technicians and large-scale analytical equipment. In addition, when analytes are complicated (e.g. samples from blood, salvia, or larynx) or have a low concentration, the pre-treatment is more difficult.
In order to improve the diagnoses, analytes are combined with magnetic particles. The user can control the analytes to move in different operating spaces by controlling an external magnetic field. Thus, the analytes combined with the magnetic particles move according to a magnetic force applied by the external magnetic field.
However, in the above controlling method, the distribution of the produced magnetic field is not uniform, so that it is hard to separate the magnetic particles from a droplet, and it is hard to produce a uniform magnetic field covering a larger area. In addition, magnetic particles may improperly adhere to the inner surface of the operating space because of greater friction between the magnetic particles and the operating space.